pytest: Add test for optional options in cln-plugin

Changelog-Added: cln-plugin: Options are no longer required to have a default value

plugins/examples/cln-plugin-startup.rs

@@ -14,7 +14,17 @@ async fn main() -> Result<(), anyhow::Error> {
             options::Value::Integer(42),
             "a test-option with default 42",
         ))
+        .option(options::ConfigOption::new(
+            "opt-option",
+            options::Value::OptInteger,
+            "An optional option",
+        ))
         .rpcmethod("testmethod", "This is a test", testmethod)
+        .rpcmethod(
+            "testoptions",
+            "Retrieve options from this plugin",
+            testoptions,
+        )
         .subscribe("connect", connect_handler)
         .hook("peer_connected", peer_connected_handler)
         .start(state)
@@ -26,6 +36,12 @@ async fn main() -> Result<(), anyhow::Error> {
     }
 }
 
+async fn testoptions(p: Plugin<()>, _v: serde_json::Value) -> Result<serde_json::Value, Error> {
+    Ok(json!({
+        "opt-option": format!("{:?}", p.option("opt-option").unwrap())
+    }))
+}
+
 async fn testmethod(_p: Plugin<()>, _v: serde_json::Value) -> Result<serde_json::Value, Error> {
     Ok(json!("Hello"))
 }

tests/test_cln_rs.py

@@ -72,6 +72,20 @@ def test_plugin_start(node_factory):
     l1.daemon.wait_for_log(r'Got a connect notification')
 
 
+def test_plugin_optional_opts(node_factory):
+    """Start a minimal plugin and ensure it is well-behaved
+    """
+    bin_path = Path.cwd() / "target" / "debug" / "examples" / "cln-plugin-startup"
+    l1 = node_factory.get_node(options={"plugin": str(bin_path), 'opt-option': 31337})
+    opts = l1.rpc.testoptions()
+    print(opts)
+
+    # Do not set any value, should be None now
+    l1 = node_factory.get_node(options={"plugin": str(bin_path)})
+    opts = l1.rpc.testoptions()
+    print(opts)
+
+
 def test_grpc_connect(node_factory):
     """Attempts to connect to the grpc interface and call getinfo"""
     # These only exist if we have rust!